Catalysts for the hydroalkylation of benzene, toluene and xylenes.
作者:TSUTOMU KAMIYAMA、SABURO ENOMOTO、MASAMI INOUE
DOI:10.1248/cpb.29.15
日期:——
The catalytic hydroalkylation of benzene over palladium and fused salt (NaCl-AlCl3) was examined under hydrogen pressure. The combination catalyst of palladium and fused salt showed good activity for hydroalkylation, providing cyclohexylbenzene as the main product, with a small amount of bicyclohexyl. With 0.24% palladium supported on alumina, suitable reaction conditions were : a temperature of 120-140°, and a reaction time of 5-10 hr in the presence of fused salt (NaCl-AlCl3 ; molar ratio 1 : 1). Under these conditions, the yields of cyclohexylbenzene and bicyclohexyl were 54.7 and 5.1%, respectively. This catalyst system was applied to the hydroalkylation of toluene, xylenes and trimethylbenzenes. Based on the behavior of the fused salt, we suggest that NaAlCl4 represents an active species in the hydroalkylation reaction.
在氢气压力下检查了苯在钯和熔盐 (NaCl-AlCl3) 上的催化加氢烷基化反应。钯和熔盐的组合催化剂表现出良好的加氢烷基化活性,主要产物为环己基苯,并含有少量联环己基。对于负载在氧化铝上的0.24%钯,合适的反应条件为:温度120-140℃,在熔盐(NaCl-AlCl3;摩尔比1:1)存在下反应时间5-10小时。在此条件下,环己基苯和联环己基的收率分别为54.7%和5.1%。该催化剂体系应用于甲苯、二甲苯和三甲苯的加氢烷基化。根据熔盐的行为,我们认为 NaAlCl4 代表加氢烷基化反应中的活性物质。